Carotid artery disease: presence of ipsilateral carotid bruits did not usefully rule stenosis in or out.

Clinical bottom line (level 1b)

  1. In carotid artery disease, patients with ipsilateral focal bruits were slightly more likely to have 70% or more stenosis (LR+1.61) , and those without were slightly less likely to have high-grade stenosis (LR-0.61) .
Sauve et al: Annals of Internal Medicine 1994; 120 (8): 633-637
Expires February 2003

The study

Setting: data was taken from the North American Symptomatic Carotid Endarterectomy Trial (NASCET) which was conducted in 57 centres, Canada and the United States

1268 patients (aged ?, 68% male) recent single or recurrent transient ischaemic attacks or nondisabling strokes judged to arise from carotid artery disease

Excluded if
  • = 80 years old
  • not fit for surgery
  • concurrent illness likely to cause death within 5 years
  • other probable cause for symptoms


    • carotid endarterectomy
    Independent blinded reference standard, applied in all patients from a ?consecutive appropriate spectrum.
    Reference standard:
    • Computed tomography of the head and neck, ultrasonography and bilateral selective carotid angiography. Angiograms were reviewed and graded by a neuroradiologist, whose intraobserver agreement was 0.89 for distinguishing 70% or more stenosis from lesser stenoses.
    Diagnostic test: Systematic history taking and physical examination, which included auscultation of the orbits, supraclavicular area an neck for focal or diffuse bruits. Focal carotid bruits were generally taken to be bruits that could only be heard over a well-localised area of bifurcation of the artery in the region of the upper border of the thyroid cartilage, whereas diffuse bruits could be heard over most of the artery's lengt5h.

    The evidence


    diagnostic test high-grade (over 70%) stenosis lesser degrees of stenosis LR+
    (95% CI)    		 post-test probability LR-
    (95% CI)    		 post-test probability
    presence of ipsilateral focal bruit 1.61
    (1.40 to 1.80)     		-% 0.61
    (0.54 to 0.69)     		-%
    total

    Comments

    1. Despite the fact readers of the angiograms were apparently not blinded to the results of the physical exam, which might have exaggerated the performance of the physical examination, the sensitivity and specificity of the presence of a bruit to diagnose severe stenosis were mediocre.

    Citation

    1. Sauve JS, Thorpe KE, Sackett DL, et al: Can bruits distinguish high-grade from moderate symptomatic carotid stenosis?. Annals of Internal Medicine 1994; 120 (8): 633-637
    Contributor: Clare Wotton and Chris Ball, February 2000
    Reviewer: Roy Poses

    Clinical Question.
    Patient cerebrovascular disease
    Intervention or Exposure cervical bruits and other clinical characteristics
    Comparison angiography
    Outcome diagnosis of high grade stenosis